Method and apparatus for scanning and storing a low resolution optical representation of a finger's image

• US 6,341,171 B1
• Filed: 01/10/1995
• Issued: 01/22/2002
• Est. Priority Date: 01/10/1995
• Status: Expired due to Fees

• Current Assignee: Qtech Systems Incorporated
• Original Assignee: Pierre De Lanauze
• Inventors: de Lanauze, Pierre
• Primary Examiner(s): Johns, Andrew W.
• Application Number:
  US08/370,979
• Time in Patent Office: 2,569 Days
• Field of Search: 382/124, 382/126, 382/125, 382/260, 382/275, 382/266, 382/237, 356/71
• US Class Current: 382/124
• CPC Class Codes: G06V 40/1347 Preprocessing; Feature extraction

Abstract

A method and apparatus for scanning and storing an optical representation of a finger'"'"'s papillary lines reduces the amount of information for storing in memory by eliminating gray scale regions of the image. An image of the finger'"'"'s papillary lines is created by a scanning device. The image is then converted to an electrical signal and filtered to reduce the image'"'"'s resolution. The resulting pattern is then converted to n bytes of digital information. A processor then selects y byte sequences, each byte sequence having m bytes, wherein the product of m and y is less than n. The selected byte sequences are stored such that when the byte sequences are detected out of the n bytes, the identity of the individual is confirmed.

Claims

1. An apparatus for creating an image to uniquely identify an individual, said apparatus comprising:

a scanner arranged to scan a fingerprint side of the individual'"'"'s finger to provide an image of the finger'"'"'s papillary lines, said image including a plurality of gray scale regions;

a converter arranged to convert said image to an electrical signal representative of said image;

a filter arranged to filter said electrical signal so that electrical representations of the gray scale regions are filtered out of the electrical signal;

an analog-to-digital (A/D) converter arranged to convert said filtered electrical signal to digital information; and

a processor arranged to select portions of the digital information such that an entirety of the image fails to be reproducible from the selected portions.

2. An apparatus as claimed in claim 1, further comprising a digital storage arranged to store the selected portions of said digital information for retrieval.

3. An apparatus as claimed in claim 2, further comprising a comparator circuit arranged to compare the digital information stored in said digital storage to authenticate an identity of an individual whose fingerprint side of the finger was scanned.

4. An apparatus as claimed in claim 1, wherein said scanner comprises a charged couple device.

5. An apparatus as claimed in claim 4, wherein said charged couple device is arranged to operate in an infrared region.

6. An apparatus as claimed in claim 1, wherein said scanner further comprises a scanning surface arranged to receive said fingerprint side of the finger to enable the formation of said image.

7. An apparatus as claimed in claim 6, further comprising light emitting diodes (LEDs) arranged to illuminate the scanning surface such that the papillary lines of said finger become illuminated.

8. An apparatus as claimed in claim 7 wherein said LEDs are arranged to operate in an infrared spectrum.

9. An apparatus as claimed in claim 1 wherein said filtering circuit comprises a noise filter arranged to reduce a resolution of the image.

10. An apparatus as claimed in claim 1, wherein the processor is arranged to receive n bytes of digital information from said analog-to-digital converter and is arranged to select a number y of byte sequences, each byte sequence having m bytes, wherein the product of m and y is less than n.

11. An apparatus as claimed in claim 10, wherein said processor is arranged to select a number of the byte sequences that are sufficient to uniquely identify the individual whose fingerprint side of the finger was scanned and yet insufficient to reproduce an entirety of the filtered image of the fingerprint side of the finger.

12. An apparatus as claimed in claim 1 wherein said filter comprises an automatic gain control and a filtering circuit.

13. A method of obtaining a digital representation of a selected region of a finger'"'"'s papillary lines, comprising the steps of:

scanning the fingerprint side of a finger to provide an image of the finger'"'"'s papillary lines, the image including a plurality of gray scale regions in the image;

converting said image to an electrical signal representative of said image;

filtering said electrical signal such that the gray scale regions of the image are removed from the electrical signal;

converting said filtered electrical signal to digital information; and

selecting portions of said digital information such that an entirety of the image is free from being reproducible from the selected portions.

14. A method as claimed in claim 13, further comprising a step of storing the selected portions of said digital information for retrieval.

15. A method as claimed in claim 13, wherein said step of scanning is carried out by scanning with infrared light.

16. A method as claimed in claim 13, wherein said step of converting includes converting said image to said electrical signal using a charged couple device.

17. A method as claimed in claim 16, further comprising illuminating said finger using light emitting diodes (LEDs).

18. A method as claimed in claim 17, further comprising operating said LEDs in the infrared spectrum.

19. A method as claimed in claim 13, further comprising the steps of comparing the digital information with stored selected portions of said digital information to determine the identity of an individual whose finger was scanned.

20. A method as claimed in claim 13, further comprising the steps of receiving n bytes of said digital information at a processor, the step of selecting including selecting a number of y byte sequences from said digital information, each byte sequence having m bytes, wherein the product of m and y is less than n.

21. A method as claimed in claim 20, wherein the step of selecting yields a number of the byte sequences sufficient to determine the identity of the individual whose finger was scanned but insufficient to reproduce an entirety of the filtered image of the finger'"'"'s papillary lines.

22. A method as claimed in claim 13 wherein said step of filtering further comprises changing the gain of said electrical signal and filtering noise therefrom.